Regulation of melanogenesis: the role of cAMP and MITF
Journal Title: Advances in Hygiene and Experimental Medicine - Year 2012, Vol 66, Issue 0
Abstract
The article presents the melanogenesis pathway and the role of cyclic adenosine monophosphate (cAMP) and microphthalmia transcription factor (MITF) in regulation of this process. Products of melanogenesis are eu- and/or pheomelanins synthesized in a multistage process of tyrosine oxidation and polymerization. The conversions require the presence of tyrosinase (TYR, key enzyme), tyrosine hydroxylase isoform I (THI) and tyrosinase related proteins (TRP1 and TRP2). Many types of signal molecules and transcription factors participate in regulation of melanin synthesis, but the most important are cAMP and MITF. cAMP is the second messenger in the intracellular signal cascade, which is synthesized from adenosine triphosphate (ATP) by adenylyl cyclase, activated among others by the melanocortin receptor and the αS subunit of G protein. The signal molecule cAMP regulates MITF, TYR, THI, GTP-cyclohydroxylase I (GTP-CHI) transcription and phenylalanine hydroxylase (PAH) phosphorylation at Ser16 by protein kinase A (PKA). Mutations of genes encoding proteins belonging to the cAMP signal cascade may lead to McCune-Albright and Carney syndromes. MITF is one of the most important nuclear transcription factors regulating melanogenesis. Currently 10 isoforms of human MITF are known, but in melanocytes only MITF-M, MITF-Mdel, MITF-A and MITF-H occur. MITF transcription factor regulates melanogenesis by activation of tyrosinase, TRP1 and TRP2 transcription. It also affects expression of other factors regulating melanosome maturation, biogenesis and transport. Moreover, it regulates melanocyte proliferation and protection against apoptosis. Mutations of the MITF gene may lead to hereditary diseases: Waardenburg type II and Tietz syndromes.
Authors and Affiliations
Michał Otręba, Jakub Rok, Ewa Buszman, Dorota Wrześniok
Keywords
Related Articles
- EP ID EP66630
- DOI -
- Views 149
- Downloads 0
Cathelicidins and defensins regulate mast cell antimicrobial activity
Cathelicidins and defensins are the multifunctional host defense molecules essential for immune response to infection. In recent years they have been shown to be natural, broad-spectrum antimicrobials against both Gram-p...
Zwiększony odsetek limfocytów supresorowych CD8+CD28– we krwi obwodowej i naciekach skórnych koreluje ze stadium zaawansowania choroby u pacjentów z chłoniakami T-komórkowymi skóry (CTCL)
Wstęp: Limfocyty CD8+CD28– są podtypem limfocytów CD8+, które pełnią funkcje regulatorowe. Zwiększona proporcja limfocytów CD8+CD28– została udokumentowana w chorobach infekcyjnych, autoimmunologicznych i nowotworowych o...
Białko wiążące retinol typu 4 (RBP4) jako czynnik i marker uszkodzenia naczyń związany z insulinoopornością
Jedną z adipokin uczestniczących w rozwoju insulinooporności jest białko wiążące retinol typu 4 (RBP-4). Fizjologiczną funkcją RBP-4 jest transport retinolu z wątroby do tkanek obwodowych. Jednym z pierwszych zaburzeń zw...
Investigations of seborrheic dermatitis. Part I. The role of selected cytokines in the pathogenesis of seborrheic dermatitis
Introduction: The etiology of seborrheic dermatitis is not fully understood. It has been observed that a number of anascogenic yeasts of Malassezia spp. is related to the intensity of the symptoms. The aim of the study i...
Skuteczność i bezpieczeństwo suplementacji witaminy D u pacjentów z przewlekłą białaczką limfocytową